I was discussing paintbrushes with someone painting gold onto ceramics this week and he said he used a very fine sable brush to get a good point and build up the yellow glaze that goes underneath the gold.
I also watched a friend painting. She was using acrylics and trying to shape some pointed areas on the painting. I looked at the brush she was using and she had a square chisel shaped brush. Although she was turning the brush on its side she could not get a good point to her painting. I suggested she used a pointed brush but a bit bigger than the tiniest brushes you can use. This is because you can load up your brush with paint. Draw the point of the brush from the area where you want a sharp angle and then use the body of the brush to fill into the shape as it widens below the point of the shape.
I tend to use blunt ended square brushes to fill in larger areas, or shape bricks etc. I use long thin brushes to try and paint straight lines. These also allow you to load a brush and keep going so the paint does not run out too quickly.
You can also use a brush when the bristles split to paint things such as feathers and hair and fur.
My favourite brushes are made with a type of plastic bristles. They tend to keep their shape and point better. Hair brushed like hog, sable and other animal hairs can be good. But it depends on how strong they are and how they are used. I sometimes repoint my brushes by putting them in my mouth and pulling them through my lips. Not recommended if you use oil paint and always make sure they have been washed clean first.
Some hair brushes immediately look like they have been electrocuted .. You know, all the hair sticking out. It’s really annoying. Or the brush bends one way instead of staying straight and keeping a nice point. Sometimes one or two hairs escape and you can get extra lines paralleling where you are painting. This can happen if you wash a brush out and leave it in the water. Just rinse it out, wipe it with tissue and put it back in your paintbox or wherever you store your brushes. If there are a few small hairs frizzing out from the brush don’t try and pull them out, just clip them off with sharp scissors. You can continue to use the brush and don’t have to throw it out.
Please don’t store brushes in a tin point down! You might have some expensive sable brushes but storing them like that. Sometimes in water! That will ruin them. If you have to store them in a water pot, empty the pot, rinse and dry the brushes and store them bristle end up.
Brushes do wear out, and eventually you cannot use them for details. But they are expensive equipment so don’t throw them away. Try using them for when you are roughing out a painting. Or even if you have a particular shape to paint, like a leaf, you can use a misshaped brush for those areas.
When washing brushes I just use clean water for water based paints. I rinse them thoroughly until the water runs clear. With oil paints I tend to rinse them first in turpentine substitute and then use a small amount of household detergent and warm water. I find rubbing the bristles in the palm of my hand is less damaging than trying to rub the paint off in the bottom of a sink.
Wow I know more about brushes than I realised!